确定beam188单元的方向

我在做钢框架模型，采用的是工字钢，但是单元方向不确定，请教高手哦！
/prep7
et,1,beam188
et,2,shell63
mp,ex,1,2.06e11
mp,prxy,1,0.3
mp,dens,1,7800
mp,ex,2,3.0e10
mp,prxy,2,0.2
mp,dens,2,2700
sectype,1,beam,i
secdate,0.6,0.6,0.9,0.022,0.022,0.014
sectype,2,beam,i
secdate,0.3,0.3,0.45,0.012,0.012,0.01
r,2,0.2
k,5000,0,9,50
k,1,
k,8,42
kfill,1,8
kgen,4,1,8,,,6
kgen,13,1,32,,,,3
/view,1,1,1,1
/angle,1,270,xm,0
/replot
建立框架柱模型。共有32根柱子，每根柱子有12条线元素构成，完成后最大线单元编号为
8*4*12=384.
*do,i,1,353,32
l,i,i+32
*enddo
lgen,8,1,12,1,6,,,1
lgen,4,1,96,1,,6,,8
latt,1,,1,,5000,,1
lesize,all,1.5
lmesh,all
lsel,u,,,all
建立外环梁模型。每层的外环梁共4根，完成后最大线单元编号为4*12+384=432
l,33,40
l,40,64
l,64,57
l,57,33
lgen,12,385,388,1,,,3,32
latt,1,,1,,5000,,2
lesize,all,2
lmesh,all
lsel,u,,,all
建立内框架梁模型。每层的内框架梁有8根，完成后最大的线单元编号为432+8*12=528。
l,41,48
l,49,56
l,34,58
l,35,59
l,36,60
l,37,61
l,38,62
l,39,63
lgen,12,433,440,1,,,3,32
latt,1,,1,,5000,,2
lesize,all,2
lmesh,all
lsel,u,,,all